The Lady Bertha is far older than her Siblings, being over a thousand years next Tuesday. She spent her early years serving her Imperator as a monster-hunter, using her powers to bind and control hundreds of unpleasant creatures and locking them within the Chancel, where they could not harm the developing civilizations of humanity. Though her body grew old and twisted, her magic became increasingly strong, and she never quite got around to dying. Now, she commands respect for her age and intelligence among the Nobilis, although she prefers to remain behind the scenes, and dislikes using her greatest powers if she can avoid it.

Bertha is manipulative, crotchety, and principally concerned with her own welfare. In general, she likes to be the power behind the throne, manipulating and assisting rather than openly asserting power. She uses her miracles to protect her Siblings, for whom she has some affection, and to control the field of action so that they can best bring their talents into play. She considers that she knows what they need better than they know themselves, and won't hesitate to interfere in their personal lives. If pushed to the absolute limit, Bertha will unleash her secret weapon, her mile-long tangle of hair, that moves at her will and can crush even the most powerful opponents.

Bertha's greatest friend is Katriana de Maxine, the Frost's-Regal, and the two often host parties and other gatherings together, sharing gossip and working together on various personal projects. However, beyond their similar dispositions and hobbies, the two have little in common, and in fact, neither one trusts the other a whit. Bertha considers that Katriana is idealistic and sentimentally attached to an imaginary memory.

The Estate of Seals controls bindings, forbiddings, locks, wards, protections, and other preventive concepts. Bertha's miracles can hold a gate shut, bind a creature not to take a certain action, or create a mystic circle that prevents entrance or exit. She can also destroy bindings with equal ease, walking into a tightly locked building as though it had no security at all.

"I don't much care for your attitude, little girl. Perhaps you'll be more respectful after you've had a chance to sleep on it for a while… I'll come back to wake you in a hundred years or so." -Bertha Blue, Seal's-Regal